The present invention relates to drug delivery articles which employ a relatively low temperature heat source to volatilize a drug for delivery. As used herein, the term "drug" includes articles and substances intended for use in the diagnosis, cure, mitigation, treatment or prevention of disease; and other substances and articles referred to in 21 USC 321(g)(1).
Over the years, there have been proposed numerous smoking products, flavor generators and medicinal inhalers which utilize various forms of energy to vaporize or heat a volatile material for delivery to the mouth of the user.
U.S. Pat. No. 3,258,015 and Australian Patent No. 276,250 to Ellis et al proposed, among other embodiments, a smoking article having cut or shredded tobacco mixed with a pyrophorous material such as finely divided aluminum hydride, boron hydride, calcium oxide or fully activated molecular sieves. In use, one end of the article was dipped in water, causing the pyrophorous material to generate heat which reportedly heated the tobacco to a temperature between 200.degree. C. and 400.degree. C. to cause the tobacco to release volatilizable materials. Ellis et al also proposed a smoking article including cut or shredded tobacco separated from a sealed pyrophorous material such as finely divided metallic particles. In use, the metallic particles were exposed to air to generate heat which reportedly heated the tobacco to a temperature between 200.degree. C. and 400.degree. C. to release aerosol forming materials from the tobacco.
PCT Publication No. WO 86/02528 to Nilsson et al proposed an article similar to that described by McCormick. Nilsson et al proposed an article for releasing volatiles from a tobacco material which had been treated with an aqueous solution of sodium carbonate. The article resembled a cigarette holder and reportedly included a battery operated heating coil to heat an untipped cigarette inserted therein. Air drawn through the device reportedly was subjected to elevated temperatures below the combustion temperature of tobacco and reportedly liberated tobacco flavors from the treated tobacco contained therein. Nilsson et al also proposed an alternate source of heat whereby two liquids were mixed to produce heat.
Despite many years of interest and effort, none of the foregoing non-combustion articles has ever realized any significant commercial success, and it is believed that none has ever been widely marketed. Moreover, it is believed that none of the foregoing noncombustion articles is capable of providing acceptable drug delivery to the user.
Thus, it would be desirable to provide a drug delivery article which utilizes non-combustion energy and which is capable of delivering acceptable quantities (eg., a dose) of a drug over at least 6 to 10 puffs.